package client;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.util.Iterator;
import java.util.Set;

/**
 * @author： YHSimon
 * @date： 2022-07-11 19:58
 */
public class ClientThread implements Runnable {
    private Selector selector;

    public ClientThread(Selector selector) {
        this.selector = selector;
    }

    @Override
    public void run() {
        try {
            for (; ; ) {
                // 获取channel数量
                int readChannels = selector.select();
                if (readChannels == 0) {
                    continue;
                }

                // 获取可用的channel
                Set<SelectionKey> selectionKeys = selector.selectedKeys();
                Iterator<SelectionKey> iterator = selectionKeys.iterator();
                while (iterator.hasNext()) {
                    SelectionKey selectionKey = iterator.next();

                    //移除set集合当前selectionKey
                    iterator.remove();
                    // 6.1 如果可读状态
                    if (selectionKey.isReadable()) {
                        readOperator(selector, selectionKey);
                    }
                }
            }

        } catch (Exception e) {
            System.out.println(e.getMessage());
        }

    }

    private void readOperator(Selector selector, SelectionKey selectionKey) throws IOException {
        // 1. 从selectionKey获取已经就绪的通道
        SocketChannel socketChannel = (SocketChannel) selectionKey.channel();
        // 2. 创建buffer
        ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
        // 3. 循环读取客户端消息
        int readLength = socketChannel.read(byteBuffer);
        String message="";
        while (readLength>0){
            // 切换读模式
            byteBuffer.flip();
            // 读取内容
            message+= Charset.forName("UTF-8").decode(byteBuffer);
            byteBuffer.clear();
            readLength=socketChannel.read(byteBuffer);
        }
        // 4. 将channel再次注册到选择器上,监听可读状态
        socketChannel.register(selector, SelectionKey.OP_READ);
        // 5. 把客户端发送消息,广播到其他客户端
        if(message.length()>0){
            // 广播给其他客户端
            System.out.println(message);
        }
    }
}
